The present invention relates generally to magnetic recording and/or reproduction, and in particular to magnetic recording on a medium having combined ferromagnetic and dielectric properties on which is provided a prerecorded pattern of capacitively detectable minute pits as a grooveless guide for controlling the track of magnetically recorded signals.
Magnetic recording has been in extensive use because of its advantages over other recording systems in versatility in recording, reading and erasing functions. Various forms of recording medium such as tape, sheet, disk and drum are now available to utilize the capabilities of magnetic recording to the fullest extent. In particular high-density recording is desired for video or digitallized audio signals.
Disks and drums are suitable media for high density magnetic recording since information can be recorded along successively arranged narrow tracks. In the past, a grooved magnetic recording medium has been developed in which the magnetic head is guided along the grooved magnetic recording track.
Various shortcomings are inherent in the grooved approach. One such shortcoming is the contact wear that exists when the magnetic head makes contact with the inner walls of the guide, resulting in a short usable lifetime. Although this shortcoming could be avoided by narrowing the width of the magnetic head while increasing its length, the magnetic head tends to wear the surface of the grooved track.
In another type of grooved magnetic recording system, the magnetic head is mounted on a forked end of a moving arm and a tracing guide follower is mounted on the other end of the fork. Guide follower engages grooved guide formed on the outer area of a magnetic recording disk and the magnetic head makes contact with a recording medium located in the inner area of the disk. A shortcoming of this type of grooved approach is the difficulty to maintain the distance between the magnetic head and guide follower constant over the range of movement between the innermost and outermost grooves.
Furthermore, it has been recognized that the grooved prior art systems fail to meet the various requirements imposed on video recording. One particular requirement is to slide the recording head over several tracks to obtain motionless or slow-motion pictures.